Perforation cleaner and washer



' Jan. 6, 1948.

L. H.- lCJASSELL PERFORATION CLEANER AND vWASHER Filed sept. 22', 1941 2 sheets-sheet 1 vll" lllIIIIllIllllllllllggugu-gng n. .A

:ATTORNEY- PERFORATION CLEANER AND WASHER Filed sept.' 22, 1941 2 sheets-sheet 2 ATTORNEY Patented Jan. 6, 194s UfNlTED- STATES PATENT vOlfFICll 2,433,828 PERFORATIGN' CLEANER AND WASHER Lloyd H.Cassell,`Los Angeles, Calif.

Application'september 22, 1941, Serial No. 411,873

(Cl. 16S-20) 10 Claims. l

The Apresent invention :relates to apparatus for lowering in the .casing vof oil wells 'with the object or cleaning and washing the perforations of liners and perforated sections of casing in the :interest of full production from lthe producing zones or areas, and-its primaryobject is the provision of a tool or apparatus of this nature which will meet all practical requirements of this character of work and enable the operator to fulfill such requirements as "they arise --in the field.

Among others,;it is an object to provide a perforation washer 'having provision vior circulation therefrom between pack off members, as well as from points above .and below the pack off area, under .full control o f the operator from the surface.

Another object is the provision of a tool of this character which may be .run into and out Q the casing without swabbing action, and may thus 'be employed for spotting slurry .and Aolierrlials in the hole.

Still another -object is vthe proyision of a tool having an automatically acting pressure booster functioning where circulation requirements `are greater than available surface ,pressure supplyE .A further .object is the provision of fa i001 of this character, theseveralfactive ,sections Vof which are interchangeably connected for shifting their `relative positions and varying the work capacity of A the tool as a Ywhole yto 4suit the known conditions under which it is used.

Other and further objects of the invent-i011. aS Well as its .details .of construction, :arrangement and operation, audits resulting advantages, may be better understood and more .thoroughly appreciated in the course of the following .description and explanation,v and by reference to the accompanying drawings, :forming va part of this vspecification, and wherein:

Figures 1, 2 'and v3 are continuing portions of a vert-ical longitudinal sectional view through the cleaning and washing tool with a full yset-up for cement incrusted perforations.

Figure 4 is a detail cross section taken therethrough substantially online 4-4 of Figure 2.

Figures A5, 6 and -'7 are continuing ver-tical longitudinal sectional views through the tool -showing a set-up` including the pressure boosting device.

Figure -8 is a vertical longitudinal section through the bull plug normally closing the lower end of the set-up ofFigures 5 and 6.

Figure 9 is a detail rvertical sectional view through a lower circulation `member for the tool, and

Figures 10 and 11 are detail transverse sectional views taken respectively on lines Ill-IIJ of Figure 5 and I I-,,I'I of Figure 6.

Referring now to these figures, the lower end portion I5 of a tubing string, upon which the tool of the present invention is lowered into an oil well casing whose -perforate section or liner is to be washed, is shown in Figures 1 and 5 as in threaded connection at `its lower end with the upper end oi the barrel II of -an upper circulating and washing section of the complete tool. This barrel I5 slidably and rotatably telescopes a circulating valve mandrel Il and has diametrically opposite radially inwardly projecting pins I8 threaded and locked in connection therewith and positioned Vin the correspondingly arranged Z- slots I9 of the mandrel, This `arrangement is such that by turning thebarrel I5 a quarter turn counterclockwise while in its lower position shown (in Fig. 1), the barrel I6 may be raised to its upper position so lthat its lower end uncovers the circulation ports 2li of the mandrel to thus permit of direct upper circulation into the casing of the well. While in its upper position, a yfurther guarter turn of barrel VIB counterclockwise moves the pins .IB into the upper transverse `portions ci the slots V,I9 and locks the Ybarrel in televated position. While the barrel ,is in its upper position it is necessary to turn the bar-rel first clockwise, then drop the same and again turn it clockwise, to lock the barrel in its normal closed position vwherein its lower portion covers and closes the circulation ports 2,0. Preferably this lower end of the barrel iB carries internal packing 2I around the mandrel I'I, with a packing nut 22 which engages an external annular shoulder 23 of the mandrel in the closed posit-ion to taire strain from the Z-slot pins I8.

The lower projecting end of mandrel I1 is preferably threaded and provided with a reduced threaded extension 24, and may be coupled by its said threads either to the yupper end of a short tubular section 25 as seen in Figure 1 which serves as a housing -for a back pressure valve 26, or to a coupling collar 2l as in Figure 5 where it is desired to supplant the back pressure valve 2 6 and Aits housing with the pressure booster shown in the Vlatter figure and described hereinafter.

` Where valve 26 and its housing 25 are used, the cage 23 of said valve is threadedly connected to the reduced extension 211 of the mandrel .I"I, and the lower end of its housing v25 is threadedly connected to vthe upper end of a bow vspring arrangement including a ktubular :bow spring sup:

port or holder 23 having external casing gripping bow springs 30, the ends of which are carried by heads 3| splined on holder 29 and engaged by springs 32 which serve to take up shocks in action and relieve the bow springs 30 of breaking strains. This bow spring and its holder serve to hold the mandrel l'i against rotation in the well casing to a suicient extent that the barrel l may be turned relative thereto, and is shown in Figures 5 and 6 in connection at its upper end by a coupling collar 33 with the lower end of the pressure booster.

On both Figures 2 and 6, the lower end of the bow spring holder 29 is shown as connected at its lower end by a coupling collar 34 with the upper end of the tubular main circulating and washing mandrel 35 which supports packing rubbers 36 and 31 externally on its upper and lower portions in selectively spaced and opposed relation above and below the intermediate circulation ports 38 of said mandrel. Through these ports 38, washing fluid under pressure in the tubing string is forced to pass laterally through the perforations of a liner or perforate section of the casing in which the washing tool is used, the high pressure area being defined between the packers 35 and 31, although the relation and spacing of the latter may be varied and nothing said here is to be taken as preventing the use of additional packers of this or similar nature at other points on the tool, arranged to provide for a similar function.Y

Within the washing mandrel 35, it will be noted a by-pass pipe 39 extends beyond the two packers 36 and 31 above mentioned, with its curved ends opening laterally through the wall of the mandrel, as at 40, respectively above and below the said packers to provide for displacement of well fluids around the packers and the high pressure circulating area therebetween, when going into and/or coming out of the hole, with the object of preventing swabbing action in the casing. Also within the mandrel 35, and having a sliding t therein, is a valve sleeve 4l. This sleeve normally rests in a position substantially below the circulating ports 38 but may be shifted in a manner presently described, to an upper position in which it covers the said ports and prevents circulation out through the same when it is desired that circulation be effected from the tool at a lower point for a purpose which will presently appear, The valve sleeve 4I preferably has a depending axial stem 42 threaded at its lower end which is shown as terminating approximately at the lower end of mandrel 35 when the valve sleeve is in lower, inactive position.

The lower end of mandrel 35 is shown in Figure 2 as connected by a coupling collar 43 with the upper end of a tubular brush holder 44 on which a brush cylinder 45 with outstanding wire or other bristles 45, is splined and confined between end springs 41 and 48 tensioning its endwise movements on the holder and absorbing any shocks incidental to such movements.

Figure 2 also shows the lower end of the brush holder 44 as connected by a coupling collar 49 to the upper end of a scraper or abrader holding cylinder 5i] on which helically curved springs 5I, equipped with abrading pieces 52, extend between heads 53 which are splined on said cylinder and confined between shock absorbing controlling springs 54 and 55.V This scraper or abrader is used Where a prior cementing operation in a well is known as probably setting up an incrustation of cement within the liner or perforate section of the casing. Such an incrustation must be removed to free the perforations for thorough washing, and this is provided for in using the scraper or abrader for removing the incrustation, followed in the downward movement of the tool by the brush cylinder whose bristles enter the perorations and serve to clean the same in a preparatory manner for the subsequent operation of the washing mandrel.

In the use of the scraper and brush which are optional features of the tool as a whole, the lower end of scraper cylinder 55 is preferably connected by a coupling collar 53 to a hollow bit head 51 having its lower end longitudinally slotted at diametrically opposed points at 53 to receive, in rotatable driving relation, the upper edge of a blade bit 53. 'This bit is normally suspended substantially below and free of the head, on an axial stem 60 which rises therefrom within the head 51 and is coupled at its upper end to a connecting stem 5 l lpassing upwardly through the scraper cylinder 55 and brush holder 44, and coupled to the lower end of the valve sleeve stern 42. Thus if the bit 59 encounters a sand bridge or cement lining in the casing, downward pressure of the tool on the arrested bit forces the head 51 downwardly into engagement with the bit so that its upper edge is within the heads slots 58 and a driving connection is affected whereby rotation of the tubing string will rotate the bit for cutting away the bridge or lining. At the same time the stem 30, 5I is shifted upwardly in the tool bore and by reason thereof, the valve sleeve 4| is thrust upwardly in the washing mandrel 35 to a position wherein it covers and closes the circulation ports 33 and thus forces circulation downwardly through the bit head 51 and outwardly around the working bit 53.

This arrangement provides for a controlled bottom circulation whereby in any case the bit 59 encounters an obstacle, the sleeve valve 4l will be raised to force circulation from the lower end of the tool and should it so happen that the lower end of the tool is, at this time, within an imperforate section of the casing, the return circulation will go around the lower section of the tool and through the by-pass 39. In the arrangement of Figures 5, 6 and 7, the bottom circulating features are shown as connected directly to the lower end of the washing mandrel 35, the bit head 51 being connected to coupling collar 43 and the bit stem S0 being connected directly to the sleeve valve stem 42.

In order to normally close off the lower circulation the bit head preferably has an internal valve seat 51a and the bit stem 60 has a conical valve member 55a which is seated on said seat when the tool is in normal run in position with the sleeve valve 4l in lower open position. Valve member 65a is thus raised when the bit encounters an obstacle, and the lower circulation is opened as the normal intermediate or washing circulation between the packers is closed by sleeve valve 4l.

However, since the brush holder, scraper cylinder and bit head and bit are optional features of the tool which are used when it is known that obstacles may be expected in entering-the perforated section of the well casing, by reason of previous cementing operations therein, these features may be eliminated in other instances, and the coupling collar 43 at the lower end of the washing mandrel used as in Figure 8 to attach thereto an ordinary bull plug 62 for closing the lower end of the tool as it is used in a washing operamember connected to the tubing and the mandrel and forming a fluid pressure supply connection therebetween, said member having therein an upper cylinder and a lower cylinder of substantially less diameter than the upper cylinder, and a pressure boosting member in said tubular member including an upper piston slidably intertting the upper cylinder, and a lower smaller piston slidably interfitting the lower cylinder, a hollow stem connecting said pistons and opening at its upper and lower ends through the pistons to form with the pistons a vertically slidable pistn assembly having a channel therethrough for the normal passage of uid pressure from the supply tubing to the mandrel, yieldable means normally urging the piston assembly upwardly in said cylinders, and a check valve in said channel of the piston assembly preventing back flow of fluid pressure from the mandrel to the supply tubing.

3. A perforation cleaning and washing tool, including a hollow mandrel for run in a well on well tubing, said mandrel having vertically spaced external packing members and laterally opening circulation ports between said packing members, a Valve for controlling said circulation ports, a tubular member below, and carried by, the said mandrel and open at its lower end, forming a bottom circulation port, a valve normally closing said bottom circulation port, and means within the mandrel and said tubular member including a shiftable stem for simultaneously opening the valve normally closing said bottom circulation port and closing the valve controlling the lateral circulation ports in the mandrel.

4. A perforation cleaning and washing tool, including a hollow mandrel for run in a .well on well tubing, said mandrel having vertically spaced external packing members and laterally opening circulation ports between said members, a valve sleeve slidable in said mandrel and normally uncovering said ports, and means connected to said valve sleeve and depending below the mandrel for engagement with a well obstruction for shifting said valve sleeve to cover said ports.

5. A perforation cleaning and washing tool, including a hollow mandrel for run into a well on well tubing, said mandrel having vertically spaced external packing members and laterally opening circulation ports between said members, a valve member slidable relative to the mandrel for covering and uncovering said ports, a tubular member below and carried by the mandrel and in open communication with the mandrel, and the lower end of which tubular member forms a bottom downwardly opening circulation port, a valve member for closing and opening said bottom circulation port, and control meansY depending through said last named valve and below said tubular member and connected to both of said valve members and operable by engagement thereof with an obstruction when sai-d tool is lowered into the well to simultaneously open one valve member and close the other.

6. A perforation cleaning and washing tool for run into a well on fluid pressure supply tubing, said tool including means forming a tubular casing in communication at its upper end with the tubing, said casing having external packing members in verticaly spaced relation and laterally opening circulation ports between said packing members, means forming upper and lower circulation ports in the casing above and below said packing members, upper and lower valves independently controlling said upper and lower circulation ports, means controllable by manipulation of the tool in a well for independently opening and closing each of said valves, means forming a fluid by-pass through the casing having its upper and lower ends opening laterally through the wall of the casing respectively above and below said packing members and between the latter and the upper and lower circulation ports, and a valved boosting member arranged in said casing and including a piston, said piston being operated by tubing pressure to force circulation outwardly through said circulation ports.

7. A perforation cleaning and washing tool for run into a well on uid pressure supply tubing, said tool comprising means forming a tubular casing in communication with the well tubing and having vertically spaced external packing members and laterally opening circulation ports between said members, said casing being also provided with a lower circulation port below said packing members, a stem, valve means on said stem, said stem being operable by engagement with an obstruction when the tool is lowered into the well to move the valve means thereon relative to the tool to open said lower circulation port and said stem being movable downwardly relative to the tool as it is lifted to cause said valve means thereon to close said lower circulation port, upper valve means arranged to open and close said laterally opening circulation ports, and means for connecting the upper and lower valve means for closing the laterally opening circulation ports when the lower circulation port is opened and for opening the laterally opening circulation ports when the lower circulation port is closed.

8. A perforation cleaning and washing tool for run into a well on fluid pressure supply tubing., said tool comprising means forming a tubular casing in communication with the well tubing and having vertically spaced external packing members and laterally opening circulation ports between said members, said casing being also provided with a lower circulation port below said packing members, a stem, valve means on said stem, said stem being operable by engagement with an obstruction when the tool is lowered into the well to move the valve means thereon relative to the tool to open said lower circulation port and said stem being movable downwardly relative to the tool as it islifted to cause said valve means thereon to close said lower circulation port, upper valve means arranged to open and close said laterally opening circulation ports, means for connecting the upper and lower valve means for closing the laterally opening circulation ports when the lower circulation port is opened and for opening the laterally opening circulation ports when the lower circulation port is closed, and means forming a fluid lby-pass through the casing independent of said lower circulation port and having upper and lower ends opening laterally through the Wall of the casing respectively above and below the upper and lower packing members, the lower end of said fluid bypass being located above said lower circulation port.

9. A perforation cleaning and washing tool for run into a well on fluid pressure supply tubing, said tool comprising means forming a tubular casing in communication with the well tubing and having vertically spaced external packing members and laterally opening circulation ports between said members, said casing also having a lower circulation port below said packing members, a stem, valve means on said stem, said stem operable by engagement with an obstruction when the tool is lowered into the well to move the valve means thereon relative to the tool to open said lower circulation port and said stem movable downwardly relative to the tool as it is lifted to cause said valve means thereof to close said lower circulation port, and means forming a fluid bypass through the casing independent of said lower circulation port and having upper and lower ends opening laterally through the wall of the 10 casing respectively above and below the upper and lower packing members, the lower end of said bypass opening above the said lower circulation port.

10. A perforation cleaning and Washing tool including a hollow mandrel to run in a well on well tubing, said mandrel having upper and lower spaced packing members thereon, and a tubular by-pass in said mandrel having its upper and lower ends opening laterally through the wall of 10 the mandrel respectively above and below said packing members, said by-pass providing for return circulation therethrough from the bottom.

LLOYD H. CASSELL.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,055,515 Yarbrough Sept. 29, 1936 2,235,318 Halliburton Mar. 18, 1941 2,239,296 Robinson Apr. 22, 1941 1,380,517 Bashara June 7, 1921 1,510,669 Halliday Oct. 7, 1924 2,297,020 Page Sept. 29, 1942 1,664,283 Boynton Mar. 27, 1928 2,215,599 .'Iullberg et al Sept. 24, 1940 

